The proposal is a request to continue and extend a NIMH- supported longitudinal study of two cohorts of families of Grade 4 boys. The first 5-year period was highly successful in obtaining cooperation of families living in high crime areas of the city. The attrition level has also been very low during the ensuing years of the project, even though all family members have participated in intensive assessment at both Grade 4 and 6 levels, with minor assessments in alternate years. The original focus on antisocial behavior has been expanded to include an effort to understand and to successfully predict both substance use and depressed mood. The study uses a multimethod (i.e., interviews, questionnaires, telephone interviews, videotaped interaction tasks with family and peers, testing and records data) and multiagent (parents, teachers, target child, peers, interviews, tape coders and raters) approach to the measurement of etiological variables (e.g., family management, family and peer substance use, peer relations) in the development of antisocial, substance abusive and depressive behaviors in male adolescents. The objective is to provide a solid empirical base for developing both prediction and prevention procedures in those three problem areas. A stage model is presented that traces out the family and peer influences involved in the child becoming increasingly at risk for remaining in a process that results in delinquency, substance use and depression. In the stage model, each new pattern of problems or omitted social skills produces, in turn, a reaction from the social environment that may further increase the risk for progressing in that process. These reactions define a set of variables thought to function as positive feedback loops for the process.